During the Open water inflow from the channel tunnel (a water pipe is not full) is Under pressure to control the Gate will be used to prevent air bubbles inside the tunnel? ?
During the water flowing into the tunnel from the Open channel (full water pipe) Under pressure to take a Gate in control to avoid air bubbles inside the tunnel or not.
In the water to flow into the tunnel from Open channel (water pipe) is a full Under pressure will use Gate control not to air bubbles inside the tunnel? How.